MEMPHIS, Tenn. — A manhunt continued Sunday following the fatal shooting of a Memphis police officer who was killed the previous night during a traffic stop, Tennessee police officials said.

Memphis Police Director Toney Armstrong said during a news conference that police were alerted about 9:18 p.m. Saturday that an officer had been shot multiple times. Armstrong said the officer was transported in critical condition to a hospital, where he died.

In a statement Sunday morning, Memphis Police identified the slain officer as Sean Bolton, 33. Police also said that a civilian had used Bolton”s radio to notify police about the shooting. No further details were released.

Armstrong said police have not made an arrest and the suspect is on the run. He said police are using all available resources to find the shooter.

Bolton was shot near one of the main arteries in southeast Memphis, an area that includes homes, apartments and businesses. Police are looking for potential witnesses and are asking for members of the public who have information about the suspect to come forward. No suspects have been publicly identified.

Armstrong said officers are grieving, adding that “this is just a reminder of how dangerous” the job is.

“Sadly to say, we”ve been here before,” he said.

Bolton is the third Memphis officer to be fatally shot in slightly more than four years. Officer Tim Warren was killed while responding to a shooting at a downtown Memphis hotel in July 2011. In December 2012, Officer Martoiya Lang was killed while serving a warrant.

Memphis Mayor A.C. Wharton Jr. said Bolton”s death “speaks volumes about the inherent danger of police work” and asked others to “pray for the family and pray for our city.” During past police shootings, both Wharton and Armstrong have said too many violent criminals are out on the street and have easy access to guns.

“The men and women in blue have certain rules of engagement that they have to follow, but at any given minute in a 24-hour day they”re dealing with folks who have no rules of engagement,” Wharton said.

The Rev. Jason Mendoza of Woodland Presbyterian Church told The Associated Press that Bolton served as the best man at the wedding of his brother, Brian Bolton, this summer. Church member Pam Haley said Bolton”s father died about a month ago. Brian is a member of the church.

During the church”s morning service, Mendoza asked worshippers to pray for the Bolton family.